The invention relates to a method for re-profiling by peripheral milling at least one running surface of a rail, preferably the convex portion of the rail head cross-profile of a rail, especially a railway rail, which convex portion exhibits the running surface.
It is known to re-profile worn rails by peripheral milling, i.e. to provide them with a new profile. For that purpose, the rail head was machined by peripheral milling. In order to somewhat control the costs of a milling cutter, it is known to equip the milling cutter with turning plates mounted to holding devices in turn inserted in recesses in the milling cutter body. In doing so, the turning plates being on a level of the peripheral milling cutter each generate a milling track oriented in the longitudinal direction of the rail. However, for lack of space, the number of turning plates to be attached is limited with peripheral milling cutters of that kind. Therefore, by peripheral milling it was only possible to provide a small number of tracks lying next to each other in the longitudinal direction of the rail and being applied to the rail head by the turning plates. Thereby, a large corrugation is created, and it was necessary to subject the rail head to a smoothing process following upon milling. It is known to equip a peripheral milling cutter for that purpose with a plurality of blades exhibiting the entire desired profile. The plurality of blades is necessary in so far as they ensure that only slight differences in depth occur in the longitudinal direction of the rail. Here, it is disadvantageous that the hollows and points generated by such kind of smoothing extend across the entire cross section that is machined. That causes noise and vibrations when being passed over as well as a decrease in lifetime.
The invention aims at avoiding those drawbacks and difficulties and has as its object to provide a method of the initially described kind as well as a rail-profile milling cutter for carrying out the method, by means of which it is possible to achieve a minor corrugation both in the longitudinal direction of the rails and in the cross-profile which complies with the regulations of the railway operators or the railway corporations. The present invention employs a milling operation thatxe2x80x94for less stringent regulation requirements, such as for slower speeds of the railwayxe2x80x94may suffice alone. To meet more stringent requirements, such as for faster speeds of the railway, an optionally subsequent grinding operation may be employed.
In a method of the initially described kind that object is achieved in that, in order to produce the desired profile by a single peripheral milling operation, more than five, preferably nine, milling tracks lying next to each other in the longitudinal direction of the rail are formed and that, in the following, optionally a grinding operation of at least the running surface, preferably the convex portion of the rail head cross-profile, which convex portion exhibits the running surface, is carried out.
Preferred variants are characterized in the subordinate claims.
As mentioned above, for railways having greater requirements such as, faster traveling speeds, the milling operation, according to the invention, is followed by a grinding operation. Thus, in order to decrease or level the corrugation running in the longitudinal direction of the tracks and, optionally, in order to flatten or level the polygonal line (cross-section), respectively, the milled rail is ground, preferably immediately following upon milling taking place in the same run. The axis of the grinding wheel and a plane perpendicular to the longitudinal direction of the rail includes an angle deviating from 0xc2x0. Preferred variants for said grinding are described in the following detailed description of the invention.
A rail-profile milling cutter according to the invention is provided for milling at least one running surface of a rail, especially a railway rail, preferably for milling the convex portion of a rail head cross-profile of a rail. The rail-profile milling cutter is a sandwich milling cutter configured with a plurality of wheels each of which is provided with turning plates at the periphery of the wheels.
Advantageous embodiments are described below
A device for carrying out the method according to the invention is characterized by
a means for generating a relative motion between the rail and the milling cutter as well as the optionally existing grinding wheel,
a driving means for the milling cutter as well as a driving means for the grinding wheel in case a grinding wheel is provided,
a milling cutter formed of a plurality of wheels provided with turning plates at the periphery,
a positioning of the axis of the grinding wheel in a direction deviating from a plane perpendicular to the longitudinal direction of the rail.